Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
History
Origin
-
Discoverer
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
Class
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Family
Group
-
Other Categories
Fine Grained Rock, Opaque Rock
Texture
Clastic
Color
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Maintenance
Less
Durability
Durable
Water Resistant
✔
✘
58% - Sedimentary Rocks Rocks have it !
Scratch Resistant
✔
✘
61% - Sedimentary Rocks Rocks have it !
Stain Resistant
✔
✘
42% - Sedimentary Rocks Rocks have it !
Wind Resistant
✔
✘
36% - Sedimentary Rocks Rocks have it !
Acid Resistant
✔
✘
19% - Sedimentary Rocks Rocks
Appearance
Dull
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing, Whetstones
Industry
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Medical Industry
-
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Other Uses
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Types
Greywacke
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
Monuments
-
Famous Monuments
-
Sculpture
-
Famous Sculptures
-
Pictographs
-
Petroglyphs
-
Figurines
-
Fossils
Present
Formation
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
Composition
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Transformation
Metamorphism
✔
✘
17% - Sedimentary Rocks Rocks
Types of Metamorphism
-
Weathering
✔
✘
78% - Sedimentary Rocks Rocks have it !
Types of Weathering
Biological Weathering, Chemical Weathering
Erosion
✔
✘
86% - Sedimentary Rocks Rocks have it !
Types of Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Physical Properties
Hardness
6-7
1
7
👆🏻
Grain Size
Angular and Fine
Fracture
Conchoidal
Streak
White
Porosity
Highly Porous
Luster
Dull
Compressive Strength
120.00 N/mm2
Rank: 26 (Overall)
0.15
450
👆🏻
Cleavage
Perfect
Toughness
2.6
Specific Gravity
2.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Density
2.6-2.61 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.71 kJ/Kg K
Rank: 23 (Overall)
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Namibia, Nigeria, South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Greenland
Deposits in Western Continents
North America
Canada, USA
South America
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand